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/* Copyright (c) 2010 The Chromium OS Authors. All rights reserved.
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*
* Tests for kernel image library.
*/
#include <stdio.h>
#include <stdlib.h>
#include "file_keys.h"
#include "kernel_image.h"
#include "rsa_utility.h"
#include "utility.h"
/* ANSI Color coding sequences. */
#define COL_GREEN "\e[1;32m"
#define COL_RED "\e[0;31m"
#define COL_STOP "\e[m"
int TEST_EQ(int result, int expected_result, char* testname) {
if (result == expected_result) {
fprintf(stderr, "%s Test " COL_GREEN " PASSED\n" COL_STOP, testname);
return 1;
}
else {
fprintf(stderr, "%s Test " COL_RED " FAILED\n" COL_STOP, testname);
return 0;
}
}
KernelImage* GenerateTestKernelImage(int firmware_sign_algorithm,
int kernel_sign_algorithm,
uint8_t* kernel_sign_key,
int kernel_key_version,
int kernel_version,
int kernel_len) {
KernelImage* image = KernelImageNew();
Memcpy(image->magic, KERNEL_MAGIC, KERNEL_MAGIC_SIZE);
image->header_version = 1;
image->firmware_sign_algorithm = firmware_sign_algorithm;
image->kernel_sign_algorithm = kernel_sign_algorithm;
image->kernel_key_version = kernel_key_version;
image->kernel_sign_key = (uint8_t*) Malloc(
RSAProcessedKeySize(image->kernel_sign_algorithm));
Memcpy(image->kernel_sign_key, kernel_sign_key,
RSAProcessedKeySize(image->kernel_sign_algorithm));
/* Update correct header length. */
image->header_len = GetKernelHeaderLen(image);
/* Calculate SHA-512 digest on header and populate header_checksum. */
CalculateKernelHeaderChecksum(image, image->header_checksum);
/* Populate kernel options and data with dummy data. */
image->kernel_version = kernel_version;
image->options.version[0] = 1;
image->options.version[1] = 0;
Memset(image->options.cmd_line, 0, sizeof(image->options.cmd_line));
image->options.kernel_len = kernel_len;
image->options.kernel_load_addr = 0;
image->options.kernel_entry_addr = 0;
image->kernel_key_signature = image->kernel_signature = NULL;
image->kernel_data = Malloc(kernel_len);
Memset(image->kernel_data, 'F', kernel_len);
return image;
}
#define DEV_MODE_ENABLED 1
#define DEV_MODE_DISABLED 0
/* Normal Kernel Blob Verification Tests. */
int VerifyKernelTest(uint8_t* kernel_blob, uint8_t* firmware_key_blob) {
int success = 1;
if (!TEST_EQ(VerifyKernel(firmware_key_blob, kernel_blob, DEV_MODE_ENABLED),
VERIFY_KERNEL_SUCCESS,
"Normal Kernel Blob Verification (Dev Mode)"))
success = 0;
if (!TEST_EQ(VerifyKernel(firmware_key_blob, kernel_blob, DEV_MODE_DISABLED),
VERIFY_KERNEL_SUCCESS,
"Normal Kernel Blob Verification (Trusted)"))
success = 0;
return success;
}
/* Normal KernelImage Verification Tests. */
int VerifyKernelImageTest(KernelImage* image,
RSAPublicKey* firmware_key) {
int success = 1;
if (!TEST_EQ(VerifyKernelImage(firmware_key, image, DEV_MODE_ENABLED),
VERIFY_KERNEL_SUCCESS,
"Normal KernelImage Verification (Dev Mode)"))
success = 0;
if (!TEST_EQ(VerifyKernelImage(firmware_key, image, DEV_MODE_DISABLED),
VERIFY_KERNEL_SUCCESS,
"Normal KernelImage Verification (Trusted)"))
success = 0;
return success;
}
/* Tampered KernelImage Verification Tests. */
int VerifyKernelImageTamperTest(KernelImage* image,
RSAPublicKey* firmware_key) {
int success = 1;
fprintf(stderr, "[[Tampering with kernel config....]]\n");
image->options.kernel_load_addr = 0xFFFF;
if (!TEST_EQ(VerifyKernelImage(firmware_key, image, DEV_MODE_ENABLED),
VERIFY_KERNEL_CONFIG_SIGNATURE_FAILED,
"KernelImage Config Tamper Verification (Dev Mode)"))
success = 0;
if (!TEST_EQ(VerifyKernelImage(firmware_key, image, DEV_MODE_DISABLED),
VERIFY_KERNEL_CONFIG_SIGNATURE_FAILED,
"KernelImage Config Tamper Verification (Trusted)"))
success = 0;
image->options.kernel_load_addr = 0;
image->kernel_data[0] = 'T';
if (!TEST_EQ(VerifyKernelImage(firmware_key, image, DEV_MODE_ENABLED),
VERIFY_KERNEL_SIGNATURE_FAILED,
"KernelImage Tamper Verification (Dev Mode)"))
success = 0;
if (!TEST_EQ(VerifyKernelImage(firmware_key, image, DEV_MODE_DISABLED),
VERIFY_KERNEL_SIGNATURE_FAILED,
"KernelImage Tamper Verification (Trusted)"))
success = 0;
image->kernel_data[0] = 'F';
fprintf(stderr, "[[Tampering with kernel key signature...]]\n");
image->kernel_key_signature[0] = 0xFF;
image->kernel_key_signature[1] = 0x00;
if (!TEST_EQ(VerifyKernelImage(firmware_key, image, DEV_MODE_ENABLED),
VERIFY_KERNEL_SUCCESS,
"KernelImage Key Signature Tamper Verification (Dev Mode)"))
success = 0;
if (!TEST_EQ(VerifyKernelImage(firmware_key, image, DEV_MODE_DISABLED),
VERIFY_KERNEL_KEY_SIGNATURE_FAILED,
"KernelImage Key Signature Tamper Verification (Trusted)"))
success = 0;
return success;
}
int main(int argc, char* argv[]) {
uint64_t len;
uint8_t* kernel_sign_key_buf = NULL;
uint8_t* firmware_key_blob = NULL;
uint8_t* kernel_blob = NULL;
uint64_t kernel_blob_len = 0;
KernelImage* image = NULL;
RSAPublicKey* firmware_key = NULL;
int error_code = 0;
if(argc != 7) {
fprintf(stderr, "Usage: %s <firmware signing algorithm> " /* argv[1] */
"<kernel signing algorithm> " /* argv[2] */
"<firmware key> " /* argv[3] */
"<processed firmware pubkey> " /* argv[4] */
"<kernel signing key> " /* argv[5] */
"<processed kernel signing key>\n", /* argv[6] */
argv[0]);
return -1;
}
/* Read verification keys and create a test image. */
firmware_key = RSAPublicKeyFromFile(argv[4]);
firmware_key_blob = BufferFromFile(argv[4], &len);
kernel_sign_key_buf = BufferFromFile(argv[6], &len);
if (!firmware_key || !kernel_sign_key_buf || !kernel_sign_key_buf) {
error_code = 1;
goto failure;
}
image = GenerateTestKernelImage(atoi(argv[1]),
atoi(argv[2]),
kernel_sign_key_buf,
1, /* Kernel Key Version */
1, /* Kernel Version */
1000); /* Kernel Size */
if (!image) {
error_code = 1;
goto failure;
}
/* Generate and populate signatures. */
if (!AddKernelKeySignature(image, argv[3])) {
fprintf(stderr, "Couldn't create key signature.\n");
error_code = 1;
goto failure;
}
if (!AddKernelSignature(image, argv[5])) {
fprintf(stderr, "Couldn't create kernel option and kernel signature.\n");
error_code = 1;
goto failure;
}
kernel_blob = GetKernelBlob(image, &kernel_blob_len);
/* Test Kernel blob verify operations. */
if (!VerifyKernelTest(kernel_blob, firmware_key_blob))
error_code = 255;
/* Test KernelImage verify operations. */
if (!VerifyKernelImageTest(image, firmware_key))
error_code = 255;
if (!VerifyKernelImageTamperTest(image, firmware_key))
error_code = 255;
failure:
Free(kernel_blob);
KernelImageFree(image);
Free(kernel_sign_key_buf);
Free(firmware_key_blob);
RSAPublicKeyFree(firmware_key);
return error_code;
}
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